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In this statement, the International Commission on Non-Ionizing Radiation Protection (ICNIRP) presents its principles for protection against adverse health effects from exposure to non-ionizing radiation. These are based upon the principles for protection against ionizing radiation of the International Commission for Radiological Protection (ICRP) in order to come to a comprehensive and consistent system of protection throughout the entire electromagnetic spectrum. The statement further contains information about ICNIRP and the processes it uses in setting exposure guidelines.

Since the original ICNIRP Statement was published in 2000, there have been significant improvements in the efficiency and radiance (i.e., optical radiation emission) of LEDs. The most important improvement is the development of 'white' LEDs that can be used as general lighting sources, which are more efficient than traditional lighting sources. LEDs emitting in the ultraviolet wavelength region have also become available and have made their way into consumer products. All these changes have led to a rise in concern for the safety of the optical radiation emissions from LEDs. Several in vitro and animal studies have been conducted, which indicate that blue and white LEDs can potentially cause retinal cell damage under high irradiance and lengthy exposure conditions. However, these studies cannot be directly extrapolated to normal exposure conditions for humans, and equivalent effects can also be caused by the optical radiation from other light sources under extreme exposure conditions. Acute damage to the human retina from typical exposure to blue or white LEDs has not been demonstrated. Concern for potential long-term effects, e.g. age-related macular degeneration (AMD), remains based on epidemiological studies indicating a link between high levels of exposure to sunlight and AMD. When evaluating the optical radiation safety of LEDs, it has now been established that published safety standards for lamps, not lasers, should be applied. Thus far, the only clear, acute adverse health effects from LEDs are those due to temporal light modulation (including flicker). Glare can also create visual disturbances when LED light fixtures are not properly designed. Further research is needed on potential health effects from short- and long-term exposure to new and emerging lighting technologies.

Use of non-ionizing radiation (NIR) for diagnostic purposes allows non-invasive assessment of the structure and function of the human body, and is widely employed in medical care. ICNIRP has published previous statements about the protection of patients during medical magnetic resonance imaging (MRI), but diagnostic methods using other forms of NIR have not been considered. This statement reviews the range of diagnostic NIR devices currently used in clinical settings; documents the relevant regulations and policies covering patients and health care workers; reviews the evidence around potential health risks to patients and health care workers exposed to diagnostic NIR; and identifies situations of high NIR exposure from diagnostic devices in which patients or health care workers might not be adequately protected by current regulations.Diagnostic technologies were classified by the types of NIR that they employ. The aim was to describe the techniques in terms of general device categories which may encompass more specific devices or techniques with similar scientific principles. Relevant legally-binding regulations for protection of patients and workers, and organizations responsible for those regulations were summarised. Review of the epidemiological evidence concerning health risks associated with exposure to diagnostic NIR highlighted a lack of data on potential risks to the foetus exposed to MRI during the first trimester, and on long-term health risks in workers exposed to MRI. Most of the relevant epidemiological evidence that is currently available relates to MRI or ultrasound. Exposure limits are needed for exposures from diagnostic technologies using optical radiation within the body. There is a lack of data regarding risk of congenital malformations following exposure to ultrasound in utero in the first trimester and also about the possible health effects of interactions between ultrasound and contrast media.

Oral session; International audience

Liposomes are very useful model membrane systems: Although they are unable to mimic all the complexity of a cell membrane, they have a well-defined chemical composition, the capacity to arrange themselves in bilayers, selectivity to ionic species and molecules, and many other useful features. Interactions can take place between this model system and electromagnetic fields (EMFs) at different frequencies, from extremely low frequency up to microwave and THz range, so that, a comparative evaluation of the observed effects with different EMF components is allowed. In this context we used cationic Carbonic Anhydrase (CA)-loaded liposomes. The CA was entrapped into these liposomes and the hydrolysis rate of substrate p-nitrophenyl acetate (p-NPA) added in the bulk aqueous phase was adopted as the index of membrane permeability changes. In fact previous kinetic experiments showed a very self-diffusion rate of p-NPA across intact liposome bilayer. Observations reported by our group evidenced that combined 7 Hz sinusoidal (Bacpeak = 50mT) and parallel static (Bdc = 50mT) magnetic fields can induce permeability changes in these liposomes. Further, we reported on the effects of 2.45 GHz microwave exposure (6 mW/g) on the permeability of these cationic liposomes. Finally, we report on the effects of 130 GHz radiation modulated at low frequency of 5, 7 and 10 Hz on the permeability of these cationic liposomes. The enzyme activity, as function of increased diffusion of p-NPA, rises from 23% to 61% over 3 min of 130 GHz radiation modulated at 7 Hz, at incident intensity of 10.5 mW/cm2, and a peak electric field of 2.6 kV/cm. The increase of the incident intensity up to 17 mW/cm2 did not further increase the enzyme activity. This biological model demonstrates an extraordinary sensibility in revealing the influence of EMFs on the lipid bilayer permeability and allowed an interaction mechanism with an ELF magnetic field to be derived.